Little Ella loves Disney princesses, so when her uncle Danny told her he'd record her singing "Let It Go" from Frozen, she seized the opportunity, and nailed it.
Danny told BuzzFeed his niece “spends hours watching the Disney numbers and practicing her routines in the corresponding princess garb, dance moves and all. And she will try as hard as possibly to match every syllable and every move.”
For reference, here's the original song by Idina Menzel, who has heard Ella's version.